One of the best decisions I've ever made in both my business and personal lives was to start running. I remember this like it was yesterday.

I was attending an executive program at Stanford University's graduate school of business back in the 1960s. Several foreign businesspeople who were also attending went out for a run every day. They asked me if I would like to join them, and I thought it sounded like fun. From that simple invitation grew a habit that has lasted a lifetime.

Running not only has kept me in good shape, but it has sharpened my focus. The benefits of physical activity on both the body and mind are well-documented. My personal experience tells me that when I don't run -- or walk briskly, as I have been more likely to do in recent years -- I lose some momentum. Running clears the cobwebs and renews energy.

Two hip replacement surgeries sidelined me for the past few years. But I just can't give it up. With my doctor's blessing, I entered and completed the Rock 'n' Roll Half-Marathon in Phoenix on Jan. 20. I didn't set any records, but that's not what matters. I finished, just as I did in 10 previous full marathons, including the 100th running of the Boston Marathon.

I saw a remarkable range of participants in the half-marathon. One guy carried the American flag for all 13 miles. I saw a blind woman tethered to a guide runner, who served as her eyes, describing the scenery and painting the picture. People pushed baby strollers for the distance. Runners dedicated their races to the memory of loved ones and causes. The motivations are endless.

Anyone who finishes a marathon -- or a half-marathon -- has won. The proof is that in earlier days, people would ask you what your time was. Now the question is, "Did you finish?"

For most runners, the key to running a marathon is to understand that it is not so much a physical as a mental challenge. Your body does not want you to run a marathon. Your mind must make you do it. Therefore, you have to develop a rationale so powerful, a determination so strong that it will enable your mind to overcome the vigorous protests of your body.

Marathon legend Grete Waitz, winner of nine New York City Marathons and two London Marathons, plus five world cross-country championships, lived by the motto: "If you give up, you lose."

The race Waitz is best remembered for is the New York City Marathon in 1992. Her time: 5:32:35. That's right, more than five hours. She ran hand-in-hand with the event founder, Fred Lebow, who was fighting brain cancer. Grete's quote after the race went something like this: "The true heroes are not us up in the front but those who are there at the back of the pack because they are there for four to five hours."

In 1987, I ran my first of five New York marathons. Approximately 23,000 runners started the race, but only 20,000 finished. The last finisher was Bob Wieland, a Vietnam veteran, who ran it in four days and two hours. He had no legs and ran on his hands. When I saw him early in the race, I knew there was no way I could not finish. True hero? You bet.

"You should run your first marathon for the right reasons because you'll never be the same person again," said Bill Wenmark, my friend and marathon coach. "You must want to do it, not do it because your boss did it or your spouse did it."

Bill has trained 3,800 first-time students and only three have not finished the marathon. A dedicated Marine, Bill has run 103 marathons and is a world-class mountain biker at age 65.

The vast majority of people who sign up to run a marathon are not competing for prize money. They are in it to prove to themselves that they can do it. That thinking carries over into so many other parts of our lives.

To me, marathons are a metaphor for life. There are challenges, obstacles, rallies, accomplishments and celebrations. The finish line is a sweet sight for any competitor.

As Booker T. Washington said: "Success is measured not so much by the position that one has reached in life as by the obstacles which he has overcome while trying to succeed."

Mackay's Moral: If you don't climb the mountain, you can't see the view.

Harvey Mackay is a Minneapolis businessman. Contact him at 612-378-6202 or e-mail harvey@mackay.com.

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